Ore separation



Patented Apr. 25, 1933 PATENT OFFICE ARTHUR J. WEER'IG AND ROBERT E. GUTKBEBTSON, OI GOLDEN, MIDRADO, ASSIGNOBS TO THE AMERICAN MEDAL COMPANY, LIMITED, OF NEW YORK, H. Y., A. OORPOBA- 'I'ION OF NEW YORK 03E SEPARATION Ho Drawing.

This invention relates to ore separation, and more particularly to selective separation by flotation. The invention is particularly adaptable to the se aration of ores comprising readily floatalile gangue minerals, such as micaceous gangues and/or talcy gangues.

The term ore is to be understood as including concentrates, slimes, tailings or other products containing mixed minerals.

An object of this invention is to provide for the selective flotation in a more eilicient and economical manner than has heretofore been practicable; and more artieularly for the separation by flotation oi respective metallic constituents of ore from the accompanying gangue and/or from each other.

The invention consists in treating the ore pulp prior to flotation with glue and alum, or with glue or alum alone, to thereby retard or inhibit the flotation of one or more of the minerals to be concentrated and/or the readily fioatable gangue minerals; thereby efiecting in an economical and more efficient manner separation of one or more constituent mineral elements from the accompanying gangue minerals.

We have discovered that glue, preferably in the form of a Water solution or emulsion, has a selective depressent efiect upon various minerals and upon all gangues, making its use valuable in selective flotation. One form of glue, which has been tried, and which is now being satisfactorily used, is a vegetable glue-a cereal drivative-the trade name of which is Coraline. It is to be understood, however, that the invention is not limited to the use of this class or pan ticular kind of glue. For example, by adding glue to the ore pulp prior to flotation, it will so alter or inhibit the readily floatable gangue minerals, such for example as micaceous and talcy gangues, that they will be depressed during flotation into the tailing or reject. and thus permit the recovery of flotation concentrates of some of the valuable minerals free from contamination of the vaiueless gangne minerals. And we have further discovered that certain minerals when treated with glue are differentially in- Application filed December 8, 1927. Serial No. 288,717.

hibited retarded in flotation in increasing degrees respectively substantially in the followin named order, and approximately to the re ative degree indicated; the respective minerals being depressed accordingly. While this is not a complete list of all ininerals affected, it will serve es an illustration in connection with one s ful embodiment of the invention as p .laed in Pecos- Evangeline ore, and to re particularly described following.

Gaicna--very little efieci if the amount of giue used is kept within certain critical limits.

Graphite--Depressed to some degree.

'imlcopyrita-Jkpressing action of glue on chalcopyrite is noticeably stronger than on gaiena.

SphaZeralte.-Depressing action of glue on resinous zinc sulfide is of very much the same degree as its efiect on chalcopyrite.

Hematite-The black zinc sulfides are noticeably depressed by glue.

Pyrite-Pyrite is noticeably depressed by the use of glue in approximately the same degree as marmatite.

MoZy5dem'te.St1-ongly depressed.

Insoluble ganguea-Glue exerts a strong depressing action on insoluble gangues in general.

Micaceous and taloy mimerala.-The micas and tales are most strongly depressed of any of the above minerals.

The fact that glue, used within certa n p redetermined limits has very little inhibiting action on galena, while acting as a strong depressent of micaceous and talcy gangue minerals, which ordinarily float even more readily than galena, makes it articularly practicable to the application 0 lead cleaning of ores, such for example as Pecos ore or other complex ores; and the fact that glue acts as a noticeable depressent of marmatite, zinc and pyrite is of additional value.

We have also discovered that alum may be used as a depressing agent when added 1n small proportions, prior to flotation, to the ore pulp containin readily flotatable gangue minerals, such or example as micaceous and/or talcy gangue minerals, to so alter the flotation properties of the readily floatable gan ue minerals that they will be depressed uring flotation into the tailing or reject and thus permit the recovery of flotation concentrates of the valuable minerals free from the contamination of the valueless gangue minerals. However, its present use or this purpose is not as practicable as the use of glue to its present relatively greater cost.

We have further discovered that the use of alum as a floatable-gangue depressant in connection with a complex ore pulp containing minerals such for example as lead, zinc and copper, possesses the added advantage of noticeably improving the flotation properties of certain minerals, such for example as copper, thereby causing said minerals to float with the lead minerals, thus separating the copper from the zinc concentrate and insuring a higher recovery of the copper with the lead concentrate than could otherwise be obtained; a condition that is most desirable for economical reasons.

The relative effect, and approximate degree of such efi'ect, on various minerals such as are contained in the above types of ore, will be listed following for the purposes of illustrating the present embodiment of the invention.

Galena.-Apparently unaffected by the use of alum.

Uhalcopym'te and copper minerals in genemZ.Floatability of chalcopyrite and copper minerals in general is noticeably improved by the use of alum.

Sphalem'te and Marmatite.Alum appears to be a weak promoter for the zinc sul- Pyrite.-Apparentl.y unafi'ected.

Insoluble gangues.-lnsoluble gangues in general are not visibly depressed.

Micaceouc and talcy minorals.vcry noticeably depressed if alum is empioyed in sufiicient quantity.

It will therefore be seen that with the use of alum in conjunction with glue, the alum activates the fioatability of copper minerals, thereby counteracting and substantially neutralizing the depressing action of the glue on such minerals, and at the same time increasing the depressing action of gangues such for example as micaceous and talcy gangues.

Following these discoveries we have found that a judicious use of a combination of glue and alum may be employed to great advantage. For example,,in the separation of complex ores such as Pecos ore, the depressing effect of glue upon chalcopyrite is of considerable disadvantage, and in such case the use of alum in addition to glue improves the flotation of such minerals as chalcopyrite, While acting cumulatively with the glue to additionally depress certain other minerals such as micaceous and talcy gangues. In such case the glue is employed primarily for the elimination of. micaceous and talcy gangue minerals, and incidentally for its inhibiting action on insoluble gangues in general, as well as on marmatlte and pyrite. Alum is added in small quantity primarily to promote the flotation of chalcopyrite and thus overcome the detrimental effect of glue in depressing the copper to some extent, and

also to exert additional depressing action on the talcy and micaceous minerals.

It is to be understood that the proportion of glue and/or alum to be used will de end upon certain variables, such for examp e as the quality and/or character of ore treated; and that the proper proportion may be ascertained by suitable tests, all of which will be understood by those skilled in the art after understanding our invention.

The following examples will serve to illustrate the advantages of the invention; and show an embodiment of the invention as practiced, for example on Pecos-Evangeline ore. It is to be noted, however, that the method of procedure in the following Example o. 1 does not comprise the novel subject matter of this invention; this example being given merel as a means of comparison to illustrate t e advantages of the invention over the method as heretofore practiced on ore of this character.

Ewample N0. 1

In this example separation by froth flotation was practiced in a manner well known to those skilled in the art, to separate the lead and zinc froths; with the exception of the aeration conditioning treatment step which forms the subject matter of copending application Serial No. 233,876 filed October 4 1927.

252O grams of Pecos (Evangeline) ore, containing mixed lead, zinc, copper and iron sulfides, was ground to an 80 mesh fineness in a ball mill with water, conditioned for 90 minutes with aeration prior to lead flotation; this conditioning being for the purpose of inhibiting the flotation of the iron minerals; which conditioning by aeration per se forms no part of the present invention, being included in the subject matter of application Serial No. 233,876 filed October 4, 1927. And the following reagents were then added in proportions enumerated Pounds Sodium cyanide per ton ore 0.25 Cresylic acid per ton ore 0.06 Potassium xanthate per ton ore 0.12

This charge was then placed in a flotation machine, and the machine started. The lead froth was then removed; time of lead flotaion 12 minutes. Then.

0.06 lbs. pine oil per ton ore 0.2 lbs. xanthate per ton ore 6 2.5 lbs. copper sulphate per ton ore, and

4.0 lbs. lime per ton ore Assays Per cent recovery For Product a 7 7 7 7 I 1 I 1 o o o o Pi) oi: zii Fii In'i. Pb Cu Zn Ins.

F J 5. 2.11 18.0 9.1 39.7 17-6 5.05 9.7 38.3 84 69 14 26 .7 1.60515 2.5 3 77 2 1.4 .51 3.5 .5 13 ll \9 -72 E wample 0. 2

In this example glue was used as inhibitor in separating the rougher lead froth, and iii the lead cleaner flotation operation glue was also used, as will be more particularly pointed out in the following procedure.

2511 grams of Pecos (Evangeline) ore. containing mixed lead. zinc. copper and iron sulfides, was ground to an 80 mesh fineness in a ball mill with water and the following reagents added in proportions enumerated:

Pounds Sodium cyanide per ton ore 0.25 Animal glue per ton ore 0.9 Cresyllc acid per ton ore 0.00 Potassium xanthate per ton ore 0.12

This charge was then placed in a flotation machine, and the machine started. The load froth was then removed; time of lead flotads tion 12 minutes. Then 0.06 lbs. pine oil per ton ore 0.2 lbs. Xanthate per ton ore 2.5 lbs. copper sulphate per ton ore, and 4.0 lbs. lime per ton ore were added to the pulp remaining in the flotation machine and the zinc froth was then removed; time of zinc flotation 15 minutes: results as follows:

5 EwampleNo. 20,

Per Assays Per cent recovery cant Pmduci 2:1 of of of of I Pb Cu Zn Ins. Pb Cu Zn Ins Headings .10D 54 2.11 15.0 9.1 21151.12 12.5 35.0 82 s 12 14.30 1 1 530 42.2 4.9 1 76 7s 3.119 1 2}71 3.3- l1 16 1D 81.71

Then the lead froth was given a cleaner tion 12 minutes.

flotation after the addition of 0.2 lbs. glue per ton ore and 0.04 lbs. cresylic acid per ton ore and the lead concentrate removed; time of lead cleaner flotation 5 minutes. The pulp dilution was approximately 4: 1 and the temperature approximately 65 F.

The results of the run are shown follow- Example N 0. 2b

Assays Per oentroeovery Pei; Product ol'to- 7 '7 0| of of of t oil 23 Ins. Pb 011 Zn In.

Pbconc 7.8 42.5 [1314.817] 63 4 7 3.38 Pbclcanertails 8.4 11.7 1.11 10.4 51.5 19 4 5 10.92

Example ,No. 3

This example illustrates a test run in which alum was used as an inhibitor, and in which ore was conditioned by aeration for a period of 90 minutes prior to lead flotation; this conditioning bein for the purpose of inhihiting the flotation of the iron minerals; which conditioningby aeration per se forms no part of the present invention, being included in the subject matter of a separate application. The test procedure is given following.

2510 grams of Pecos (Evangeline) ore, containing mixed lead. zinc, copper and iron sulfides, were ground to an 80 mesh fineness in a ball mill with water and the following reagents added in proportions enumerated:

Pounds Sodium cyanide per ton ore 0.25 Alum per ton ore 4.10 Cresylic acid per ton ore 0.06 Potassium xanthate per ton ore 0.12

This charge was then placed in a flotation machine, and the machine started. The lead froth was then removed; time of lead flota- Then 0.06 lbs. pine oil per ton ore 0.2 lbs. xanthate per ton ore 2.5 lbs. copper sulphate per ton ore. and 4.0 lbs. lime per ton ore were added to the pulp remaining in the flotation machine and the zinc froth was then removed; time of zinc flotation 15 minutes. The pulp dilution was approximately 4:1 and the temperature approximately 65 F.

The results of the run are shown following:

Example No. 4

Pounds Sodium cyanide per ton ore 0.25 Cresylic acid per ton ore 0.06 Potassium xanthate per ton ore 0.12

This charge was then laced in a flotation machine, and the mac ine started. The lead froth was then removed; time of lead flotation 12 minutes. Then 0.06 lbs. pine oil per ton ore 0.2 lbs. xanthate per ton ore 2.5 lbs. copper sulphate per ton ore, and 4.0 lbs. llme per ton ore were added to the pulp remaining in the flotation machine and the zinc froth was then removed; time of zinc flotation 15 minutes.

Example No. 44

Assays Percautrecovery Pu; can Product a ol 0! of o! are: are? on Zn In Hand! 100 5.4 21118 30.7 17.2 5. 9.7213811 84 60 14 2G 0.71.0535 2.5 8 I) 77 2 1.4 .61 3.5 56.5 13 ll 0 72 Then the lead froth was. given a cleaner flotation after the addition of 0.3 lbs. glue per ton ore and 1.5 lbs. alum per ton ore and 0.04 lbs. cresylic acid per ton ore and the lead concentrate removed; time of lead cleaner flotation 5 minutes. The pulp dilution was approximately 4:1, and the temperature approximately 65 F.

The results of the run are shown followmg:

Example N0. 4b

Assays Per cent recovery Pert can 0! Per Per Per Per of or of tom :3? 8 Pb Cu Zn Ins.

Pbeonc 11.7 30.8 10.3 12.9 11.0 68 55 8 3 Pbcleaner tails"-.. 13.7 6.4 2.37 7.0 61-5 l 6 For purposes of comparing the relative merits of the respective examples above g ven, a resum of each of the above tests is given folowing in combined tabulated form.

Tabulation crude Pb concentrates Assays Per cent recovery Test Per Per cent 1. Without glue or alum Tabulation cleaned Pb concentrates Assays Per cent recovery Olean- Primary a PM cent Cu W 1 Par cont of o! ol' 0! Cu Inst 2. wan l. W l t glue.

glue. no and alum.

lue-.. out

can

It will be seen from the composite table above that in Example No. 1 where no glue or alum were used a larger amount of copper and a greater proportion of zinc and a greater amount of insolubles were carried over with the lead concentrate than was the case in Example No. 2 where glue was used as inhibitor. It will be seen that in Test No. 3 where alum was used in place of glue a larger ro ortion of copper was carrie over in the ca concentrate than in either the case without the use of glue or with the use of glue, and that the insolubles carried over were less than in either Tests 1 or 2. It will further be noted that 'in Test 4 where alum and glue were used, the insolubles were cut down from 3.38 to 3., being due to the additive inhibitory efi'ect of the alum, and by the use of alum 55% of copper was carried over with the lead concentrate as against 8% with the use of glue only; thereby clearl illustrating the varlous advantages pointe out hereinbefore; and illustrating a greatly improved selectivity which is possible in lead flotation by the use of this invention.

Another important feature of the invention, which is illustrated in the table setting forth the differential inhibitory efi'ect pro duced respectively on the various minerals of a complex ore by the use of glue, is that marmatite is noticeably depressed by the addition of glue prior to flotation; and this is of importance due to the fact that marmatite is comprised of a combination of zinc and iron sulfides, and it is particularly desirable to inhibit the flotation of the iron contained in the marmatite. And likewise, and for the same purpose, the depressing effect on pyrite, by the use of glue, is highly advanobvious to those skilled in the art, after understanding our invention, that various changes and modifications may he made therein without departing from the spirit and scope of our invention, and we aim in the appended claims to cover such changes and modifications as are within the scope of the invention.

What we claim as new and desire to secure by Letters Patent is:

1. Method of separation by flotation of gangue from other minerals, which consists in adding to the ore pulp containing lead, cop r and readily floatable gangue, prior to otation and in addition to suitable flotation agencies a small proportion of the glue suflicient to inhibit the flotation of said copper and said readily floatable gangue.

2. Method of separation of ore containing lead, copper and readily floatable gangue material which consists in separating valuable lead minerals by the a ncy of suitable flotation agents while inhi itin the flotation of copper and relatively value ess gangues composed of materials other than metallic sulfide otherwise floatable, such as micaceous and talcy gangues, by addition to the ore pulp prior to flotation of a small proportion of glue to thereby depress said copper and gangue minerals.

3. Methoa of ore separation by froth flotation, which consists in selectively separating thegangue from other mineral constitutents of said ore by the use of flotation agents while differentially reducing the flotation properties of some of said minerals by addition prior to flotation of a small proportion of glue to depress the gangue andalso adding prior to flotation a small proportion of alum to thereby substantially neutralize the said reduction of the flotation property of at least one of said minerals other than the gangue.

4. Method of selective separation by froth flotation of complex ores containing lead, copper, and normally readily floatable gangue by the use of. suitable flotation agen cies, which comprises adding prior to flotation glue which acts as a strong depressant' of said floatable gangues and also as a depressant of said copper and in such roportion as not to substantially affect the otation properties of lead, and adding also prior to otation a small proportion of alum which oppositely afiects the flotation property of saidcopper substantially to the same degree and also acts as a further depressant of said gangues, while leaving susbtantially unafiected the flotation properties of said lead, whereby the flotation properties of said lead and 00 per are substantial! nnafiected and the ibition to flotation 0 said gauges is greatly improved. a y

5. Method of separating lead sulfide from an ore containing copper and normally readily floatable gan e composed of material other than metallic sulfide by froth flotation by the use of suitable flotation agencies, which comprises adding prior to flotation two agents which act cumulatively to inhibit the flotation of said copper and said gangue consisting of matter other than metalhc sulfide while leaving substantially unaflected the flotation of said lead sulfide.

6. Method of separation by flotation of gangue from metallic sulfides, which consists in addin to the ore pulp containing copper and rea ily flotatable gangueminerals belonging to the group of micaceous and talcy gangues rior to flotation and in addition to suitable otation agencies a small proportion of glue suflicient to inhibit the flotation of said copper and said readily floatable gan es.

7. Method of separation by froth flotation of readily fioatable gangue minerals from other valuable minerals, which consists in separating lead and copper constitutents of said minerals by the use of flotation agents, one of which is glue, and each of said agents affecting differently the flotation properties of said lead and copper, and each of said agents acting cumulatively to depress the readily floatable gangue.

8. Method of selective separation by froth flotation of complex ores containing lead, pp gangue by the use of suitable flotation agencies which comprises adding prior to flotation material which acts as a strong depressant of said floatable gangues and also a depressant of said copper and in such proportion as not to substantially affect the flotation roperties of lead, and adding also prior to otation a small proportion of material which oppositely affects the flotation property of said gangues, while leaving substantially unaffected the flotation properties of said lead, whereby the flotation properties of said lead and copper are substantially unafl'ected and the inhibition to flotation of said gangues is greatly improved.

9. A process of the kind described which comprises adding to the ore pulp containing lead and floatable talcy gangue in addition to suitable flotation material, a small proportion of materials selected from a group consisting of glue and alum, and floating the lead while depressing the talcy gangiie.

'10. A process of the kind described which comprises adding to ore pulp containing lead, iron sulfides and gangue material other than sulfide and in addition to suitable flotation and normally readily floatable III material, asmall proportion of glue and floating'the lead while depressing the iron and gangue.

In testimony whereof we have signed our names to this specification.

ARTHUR J. WEINIG. ROBERT E. CUTHBERTSON.

CERTIFICATE or comuzcnon.

Patent No. 1,906,029. April 25, 1933.

ARTHUR J. WEINIG, ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, line 40, for "fiotation" read "flotation", and line 51, before "retarded" insert the word "or"; page 2, line 10, after "glue" insert "due"; and lines 109 and 121, for the Serial No. "233,876" read "223,876"; page 4. line 60, in the boxed, heading, column 4, for "Cu" read "Cu", and line 68, for "folowing" read "following"; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the ease in the Patent Office.

Signed and sealed this 13th day of June, A. D. 1933.

M. J. Moore.

(S al) Acting Commissioner of Patents.

material, asmall proportion of glue and floating'the lead while depressing the iron and gangue.

In testimony whereof we have signed our names to this specification.

ARTHUR J. WEINIG. ROBERT E. CUTHBERTSON.

CERTIFICATE or comuzcnon.

Patent No. 1,906,029. April 25, 1933.

ARTHUR J. WEINIG, ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, line 40, for "fiotation" read "flotation", and line 51, before "retarded" insert the word "or"; page 2, line 10, after "glue" insert "due"; and lines 109 and 121, for the Serial No. "233,876" read "223,876"; page 4. line 60, in the boxed, heading, column 4, for "Cu" read "Cu", and line 68, for "folowing" read "following"; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the ease in the Patent Office.

Signed and sealed this 13th day of June, A. D. 1933.

M. J. Moore.

(S al) Acting Commissioner of Patents. 

